Evolution in the Bottling of Cabernet Sauvignon Wines Macerated with Their Own Toasted Vine-Shoots.

This work studies, for the first time, the effect of the use of Cabernet Sauvignon vine-shoots as an enological additive (called "Shoot Enological Granule", SEG) in wines of the same variety. SEGs were added in two doses (12 and 24 g/L) at the end of malolactic fermentation, and after that, wines were bottled for six months. The phenolic and volatile composition and sensory profiles of wines were analyzed at bottling and after six months. The results showed a decrease in the total content of phenolic compounds with bottle time; however, stilbenes─specifically trans-resveratrol─were maintained at significant levels in SEG wines. In contrast, the total content of volatile compounds, mainly esters, increased with bottle aging. Finally, in terms of sensory profile, SEG wines showed a clear differentiation between the descriptors and the control, with more-integrated aromas after bottle time with more toasted, nutty vanilla notes, as well as silkier and less bitter tannins, compared to the control.

Toasted Vine Shoots as an Alternative Enological Tool. Impact on the Sensory Profile of Tempranillo Wines during Bottle Aging.

The use of toasted vine shoots (SEGs) as an enological tool is a new practice that seeks to improve wines by differentiating between them and encouraging sustainable wine production. The sensorial impact during bottle aging of wines treated with SEGs is a key factor to consider. This paper studies the influence of SEGs on Tempranillo wines treated with their own SEGs in two different doses (12 and 24 g/L) at two differences moments (during alcoholic fermentation and after malolactic fermentation) throughout 1 year of bottle aging. The results indicate that addition moment is the factor that most affects the evolution of sensorial descriptors. The greatest evolution in the wines was observed during the first 4 months, wherein improved integration of the notes related to addition of SEGs occurred. A reduction in the perception of dryness and bitterness was observed in the treated wines, therefore, SEGs could be considered accelerators to eliminate these initial sensations from wines.

Pruned vine-shoots as a new enological additive to differentiate the chemical profile of wines.

For this study, Tempranillo wines were made by adding their own toasted vine-shoots (SEGs, "Shoot- Enological - Granule"). The SEGs were added in two doses (12 and 24 g/L) at three different times (before alcoholic fermentation, in the middle of alcoholic fermentation, and after fermentations) and phenolic, volatile, and mineral composition were analysed. Results showed a decrease in the total content of phenolic compounds but stilbenes, specifically trans-resveratrol, increased in all wines macerated with SEGs, as did total anthocyanins when these additives were added in the middle of fermentation. Furthermore, the ratios related to glycosylated monomeric anthocyanins were significantly higher in wines treated with SEGs. The use of SEGs did not affect the total content of volatile compounds. However, changes in terms of individual compounds resulted in an odorant series associated with SEGs, named "sweet woody", formed by compounds such as ethyl vanillate, ethyl cinnamate, and vanillin. Finally, the mineral composition of the wines was not affected using SEGs, whereby potassium was the most abundant in all the wines.

Spraying ozonated water on Bobal grapevines: Effect on grape quality.

Ozone is a powerful oxidant that is increasingly used as sanitizing agent in the wine industry and even in the vineyard to control grapevine diseases. In this study, we evaluated the effect on grape enological quality of ozonated water spraying treatments carried out in Bobal grapevines during two consecutive harvest seasons. In the first season, ozonated water was applied once during the ripening period on grapevines trained on the traditional gobelet system (S1). In the second season, ozonated water was applied three times between the fruit set and harvest on grapevines grown on a vertical trellis system (S2). Grape quality on harvest day was evaluated through several enological and chromatic parameters, the phenolic maturity, the Varietal Aroma Potential Index (IPAv) and the phenolic and volatile composition. The S1 treatment had a positive effect on the technological maturity, the chromatic parameters, the seed maturity and the content of glycosylated aroma precursors, phenolic compounds and free terpenoids of grapes. The S2 treatment also improved the technological maturity and the content of total anthocyanins (pH 1.0) and free terpenoids, but had a negative impact on the chromatic parameters, the anthocyanin extractability and the content of glycosylated aroma precursors and phenolic compounds. Therefore, ozonated water sprayed on Bobal grapevines affected the quality of grapes, but the effect seemed to depend on the number of applications.

The impacts of temperature, alcoholic degree and amino acids content on biogenic amines and their precursor amino acids content in red wine.

The aim was to study how factors such as temperature, alcoholic degree, and amino acids supplementation are able to influence the content of tyramine, histamine, 2-phenylethylamine, tryptamine and their precursor amino acids in winemaking process. Biogenic amines and amino acids were quantified at the beginning, middle and end of alcoholic fermentation, and at the end of malolactic fermentation. In general, samples produced with amino acid supplementation did not show the highest concentrations of biogenic amines, except for histamine, which content increased with the addition of the four amino acids. The synthesis of tyramine was mainly affected by the temperature and alcoholic degree, the formation of phenylethylamine was largely influenced by alcoholic degree, and tryptamine synthesis principally depended on temperature. Interestingly, there was interaction between these three factors for the biogenic amines studied. In conclusion, winemaking conditions should be established depending on the biogenic amine which synthesis is required to be controlled.

Moscatel vine-shoot extracts as a grapevine biostimulant to enhance wine quality.

Non-aromatic vine-shoot extracts (Airén) has been recently proposed as "viticultural biostimulants" when applied to grapevine. In this paper, the application of extracts from non-toasted (MVS) and toasted (MVSToasted) vine-shoots from the well-known aromatic variety such Moscatel were applied on Airén grapevine leaves, observing an increased for grape yield and wines with a lower alcohol degree. All wines at the end of the alcoholic fermentation were characterized by their fruity and floral descriptors, especially MVS wines; and 4 months later, MSV and MVSToasted wines surprised by their higher spicy notes, which correspond with the highest OAVs values for compounds such as norisoprenoids (ß-damascenone), vanillin derivatives (vanillin, acetovanillone) and volatile phenols (guaiacol, syringol), compared to control wine. Wine phenolic composition was affected positively over all by MVS in case of phenolic acids. These results confirm that Moscatel vine-shoot extracts foliar application into Airén non-aromatic grapevines produce an interesting enhance on wine quality.

Effect of toasting on non-volatile and volatile vine-shoots low molecular weight phenolic compounds.

Low molecular weight phenolic compounds (LMWPC), including non-volatile and volatile, of Airén and Moscatel vine-shoot cultivars waste submitted to different toasting conditions (light, 180°/15min; medium, 180°/30min; high 180°/45min) were studied in order to exploit them with oenological purposes. The LMWPC differences were mainly due to the toasting times rather than vine-shoot variety. In non-volatile LMWPC fraction, flavanols and almost all phenolic acids decreased by toasting. The presence of trans-resveratrol has a special relevance at light toasting: 14 times more concentrated in Airén and 6 times in Moscatel vine-shoots, than their respective non-toasted samples. The volatile LMWPC showed a significant increment with toasting, being vanillin the one with the highest difference respect to non-toasted samples at high conditions: more than 15 times in Airén and 11 in Moscatel. Although toasting reduced some LMWPC, particular characteristics of these vine-shoots must be taken into account when considering its future use.

Vine-shoot waste aqueous extract applied as foliar fertilizer to grapevines: Effect on amino acids and fermentative volatile content.

The aim of this work was to study the influence of foliar applications of different wood aqueous extracts on the amino acid content of musts and wines from Airén variety; and to study their relationship with the volatile compounds formed during alcoholic fermentation. For this purpose, the foliar treatments proposed were a vine-shoot aqueous extract applied in one and two times, and an oak extract which was only applied once. Results obtained show the potential of Airén vine-shoot waste aqueous extracts to be used as foliar fertilizer, enhancing the wine amino acid content especially when they were applied once. Similar results were observed with the aqueous oak extract. Regarding wine fermentative volatile compounds, there is a close relationship between musts and their wines amino acid content allowing us to discuss about the role of proline during the alcoholic fermentation and the generation of certain volatiles.

Factors influencing the formation of histaminol, hydroxytyrosol, tyrosol, and tryptophol in wine: Temperature, alcoholic degree, and amino acids concentration.

The validation of a HPLC-PDA-MS/MS chromatographic method for the quali/quantitative characterization of histaminol, hydroxytyrosol, tyrosol, and tryptophol in wine has been described and discussed. Four standards showed a good linearity with high correlation coefficient values (over 0.9989) and LOD and LOQ were 0.001-0.015 mg/L and 0.004-0.045 mg/L, respectively. Furthermore, this study reported how factors such as temperature, alcoholic degree, and amino acids concentration are able to influence the formation of these four alcohols in Monastrell wines. The quantification values of these alcohols has been detected both at the half and end of alcoholic fermentation, and at the end of malolactic fermentation. In relation to interactions between factors, several significant variations emerged (p ⩽ 0.001). The impact of amino acids supplementation in Monastrell must it has been demonstrated, mainly in regards to histaminol and tryptophol.

Influence of the use of fungicides on the volatile composition of Monastrell red wines obtained from inoculated fermentation.

The influence of six fungicides (famoxadone, fenhexamid, fluquinconazole, kresoxim-methyl, quinoxyfen and trifloxystrobin) on the volatile composition of red wines obtained from inoculated fermentation was studied. Although treatments were carried out under critical agricultural practices (CAP), the residues in the wines were below their maximum residue limit (MRL). Ethyl decanoate was the compound most influenced by these fungicides, while diethyl succinate, decanoic acid, ß-ionone, and citronellol concentration were not changed with any of the treatments. The treatment of grapes with trifloxystrobin induced changes in only one volatile compound, and the variation in volatile composition of wines from grapes treated with fenhexamid, fluquinconazole and quinoxyfen compared to control wines was almost negligible invaluable. The treatment with famoxadone influenced more volatile compounds than the other ones, except for wine from grapes treated with kresoxim-methyl, which was the only wine that showed a big change in its aromatic composition.

Effect of vine foliar treatments on the varietal aroma of Monastrell wines.

The effects of four vine treatments, comprising the application of eugenol and guaiacol (individually or as a mixture) or whiskey lactones on the concentration of glycosidically bound aroma precursors, determined as glycosyl glucose content by HPLC-IR, in Monastrell grapes and their wines were studied. The impact of treatments on the free varietal wine aroma determined by SBSE-GC-MS and descriptive analysis after alcoholic and malolactic fermentations and six months of ageing were also determined. A synergistic effect was observed between the eugenol and guaiacol on the glycosidically bound aroma precursor fraction. The rate of release of such aroma precursors was time and treatment dependent. The impact on wines varietal aroma at the end of the alcoholic fermentation was reduced by treatments, whereas the opposite effect was observed in the following samplings. At a sensory level, the wood/oak notes were appreciated in all wines; however, the typicity of the Monastrell variety was especially enhanced at the end of the malolactic fermentation, in the wines from whiskey lactone treatment.

Haloanisole and halophenol contamination in Spanish aged red wines.

This is the first study to be carried out on the incidence of halophenols and haloanisoles, including trichloroanisole, in aged red wines. A total of 966 red wines, aged for 6, 12 and 24 months in oak barrels and from different Spanish production areas, were analysed by stir bar sorptive extraction followed by gas chromatography/mass spectrometry (GC/MS). From the wines sampled, 155 (16.1%) were contaminated with one or several compounds, with 7.6, 6.9 and 1.5% corresponding to the 12- (aged-12), 6- (aged-6) and 24-month-aged (aged-24) wines, respectively. The most abundant compounds causing taint were 2,3,4,6-tetrachloroanisole and 2,4,6-trichloroanisol (6.8 and 5.3%, respectively). No 2,4,6-tribromophenol was found in any of the samples. Contamination with halo compounds was highest in samples from South-West Spain, followed by those from Northern Spain. The mean concentration for all compounds were always higher than their respective olfactory threshold, but none of these halo compounds represent a health hazard to humans through the consumption of commercial red aged wines.

Transformation ability of fungi isolated from cork and grape to produce 2,4,6-trichloroanisole from 2,4,6-trichlorophenol.

The ability of eight fungal strains to transform 2,4,6-trichlorophenol (TCP) to 2,4,6-trichloroanisole (TCA) was studied. These fungi were isolated from cork, belonging to the genera Penicillium, Aspergillus, Trichoderma and Chrysonilia, and from grapes Botrytis cinerea. All, except Chrysonilia, produced TCA when grown directly on cork in the presence of TCP, Aspergillus and Botrytis cinerea being the ones with the highest level of production. It is the first time that Botrytis cinerea, a microorganism often present on grapes and in winery environments, has been shown to transform TCP into TCA. This result can partially explain the wine cork taint before being bottled.

A new approach to saffron aroma.

The aroma of saffron has received much attention from scientists in recent years, not only for the compounds that make it up, but also for its glycosidic precursors. Despite it all, the volatile generation mechanisms of the spice are almost completely unknown. Only the generation of safranal, the major compound, from picrocrocin has been established. The great effort carried out to detect and identify the volatile compounds of saffron has not been enough to clarify which compounds are responsible for saffron aroma. In general, scientists has devoted little attention to the sample analyzed, taking for granted that all saffron is the same, something that makes it difficult to establish a comparison between the results obtained by the different authors, to the point that saffron aroma has not been defined yet. It must be clarified whether saffron aroma is what the consumer perceives via nasally when a container of the spice is uncovered, or whether on the contrary, it is the aroma conferred to food, normally after a thermal cooking process, and perceived retronasally. After an extensive bibliographic research, simple assays are suggested to understand what could be considered as saffron aroma, results that may help to delimit the research for future studies.

Analysis of wine primary aroma compounds by stir bar sorptive extraction.

Due to the great importance of some primary aroma compounds on wine quality, these compounds which includes terpenes, C(13)-norisoprenoids and C(6) compounds, have been analyzed by stir bar sorptive extraction (SBSE) followed by a thermal desorption-gas chromatography-mass spectrometry analysis. The stir bar sorptive extraction method was optimized in terms of temperature, time, pH and NaCl addition. The best SBSE sorption kinetics for the target analytes were obtained after submitting the solutions to 60 degrees C during 90min. The addition of sodium chloride did not enhance the volatile extraction. The method proposed showed good linearity over the concentration range tested, with correlation coefficients higher than 0.98 for all the analytes. The reproducibility and repeatability of the method was estimated between 0.22 and 9.11%. The detection and quantification limits of all analytes were lower than their respective olfactory threshold values. The application of this SBSE method revealed that monovarietal white wines were clearly separated by two canonic discriminating functions when grape varieties were used as differentiating variable, the first of which explained 98.4% of the variance. The compounds which contributed most to the differentiation were limonene, linalool, nerolidol and 1-hexanol.

Stir bar sorptive extraction for the determination of volatile compounds in oak-aged wines.

Stir bar sorptive extraction (SBSE) followed by a thermal desorption-gas chromatography-mass spectrometry analysis has been optimized for the determination of 13 of the most important oak volatiles in wine samples, all in a single run. The stir bar sorptive extraction method was optimized in terms of temperature, time, pH and NaCl addition, and the best results were obtained after stirring the wine sample with the polydimethylsiloxane stir bar during 90min at room temperature. The addition of sodium chloride did not enhance the volatile extraction. The method proposed showed good linearity over the concentration range tested, with correlation coefficients ranging from 0.92 to 0.99 for all the analytes. The reproducibility and repeatability of the method was estimated between 0.11 and 5.45%. The detection and quantification limits of all analytes were lower than their respective olfactory threshold values, and, most importantly, no artifacts have been observed during the analysis as described in most extractions using other current methodologies.

Stir bar sorptive extraction for the analysis of wine cork taint.

A magnetic stir bar with a polydimethylsiloxane coating was used to absorb 2,4,6-trichloroanisole, 2,3,4,5-tetrachloroanisole, pentachloroanisole and their respective phenols from synthetic and real wine samples. The stir bar sorptive extraction method was optimised to obtain the best extraction conditions in terms of temperature, time, pH and NaCl addition. The stir bar was desorbed in a thermal desorption system coupled to a gas chromatograph-mass spectrometer. The method proposed showed good linearity over the concentration range tested and correlation coefficients ranged from 0.96 to 0.99 for all the analytes. The reproducibility and repeatability of the method was estimated between 1.29 and 4.02%. With no a pre-concentration step and with a much reduced analysis time, all the analyzed compounds showed detection and quantification limits that were lower than those observed with other methods found in the bibliography. Except for pentachlorophenol due to its poor absorptivity in polydimethysiloxane, in red wines, LOD ranged between 7.56 and 61.56 pg/l, and LOQ ranged between 17.21 and 205.11 pg/l; while in white wines, the LOD ranged between 5.82 and 30.50 pg/l and LOQ ranged between 19.41 and 101.61 pg/l. These concentrations were always lower than their respective olfactory thresholds values.

Effect of pesticide residues on the aromatic composition of red wines.

The influence of pesticide residues on the aromatic composition (major and minor volatiles) of red wines made from Vitis vinifera (Monastrell var.) was studied by comparing the concentration of aromas in wines made from grapes subjected (or not) to phytosanitary treatment with chlorpyrifos, fenarimol, mancozeb, metalaxyl, penconazole, and vinclozolin, according to the agricultural practice of the area. The analytical determination of the major volatiles was made by gas chromatography using a flame ionization detector, while the minor volatiles were determined by adsorption-thermal desorption gas chromatography using a mass selective detector. There were significant differences between the ethyl acetate, methanol, isobutanol, and diethylacetal levels of the control wine and that containing chlorpyrifos residues, although only the ethyl acetate exceeded the olfactory threshold. With regard to the minor volatiles, significant differences were detected in the concentrations of some esters, aldehydes, and acids. However, only isoamyl acetate exceeded the olfactory threshold in wines containing residues of chlorpyrifos, fenarimol, and vinclozolin.

Method to determine the authenticity of aroma of saffron (Crocus sativus L.).

A thermal desorption-gas chromatography-mass spectrometry technique was applied to 252 different Spanish saffron samples (from La Mancha and Teruel). The average safranal content made up of 60% of the volatile fraction of the saffron. All the chromatograms obtained showed an interval between 8 and 18 min (retention time of safranal +/- 5 min) in which the silhouette of the chromatographic peaks was similar in all the samples. Therefore this interval can be used as a "fingerprint." Two examples are given which demonstrate the ability to use this "fingerprint" to detect adulteration.